C program for Fibonacci series using a loop and recursion. Using the code below you can print as many terms of the series as required. Numbers of this sequence are known as Fibonacci numbers. The first few numbers of the series are 0, 1, 1, 2, 3, 5, 8, ...,. Except for the first two terms of the sequence, every other term is the sum of the previous two terms, for example, 8 = 3 + 5 (addition of 3 and 5). This sequence has many applications in Mathematics and Computer Science.